1. Field of the Invention
The present invention relates to a ligature and suture device for medical application that is inserted into a body and performs ligaturing or suturing or the like of biomedical tissue.
2. Description of Related Art
In recent years, the treating of biomedical tissue of a body using peroral endoscopy has increased. For example, a method of forming an artificial valve is known as a treatment for disorders such as gastroesophageal regurgitation in which the functioning of the active muscles of the lower esophagus deteriorates and gastric acid is regurgitated into the esophagus.
Here, a device exists that forms an artificial valve by ligaturing biomedical tissue so as to cause it to bulge out under observation using an endoscope (see, for example, Patent Documents 1 and 2).
In the system described in Patent Document 1, two needles for piercing the biomedical tissue are provided. A sheath that can be moved freely backwards and forwards is inserted into each needle. Furthermore, bar-shaped T-bars are fitted internally in the vicinity of the distal end of each needle. Suture thread is fixed to these T-bars. When an artificial valve is being formed using biomedical tissue, the biomedical tissue is suctioned and the resultant bulging biomedical tissue is punctured by the respective needles that point inwards from the operator side. Thereafter, the T-bars are pushed out from the needles using a pusher tube and the needles are then withdrawn. The two suture threads that penetrate the biomedical tissue are then tied, and the knot is pushed into the body using a typical knot pusher, so that the biomedical tissue on the operator side is ligatured.
Moreover, in Patent Document 2, a suture apparatus is disclosed that is provided with a needle operating section that has two needle sliders, a pusher slider, and a housing, and that is provided integrally via a base member with a grip, and with a ligature tool that is provided independently from the needle operating section.    (Patent Document 1) Japanese Unexamined Patent Application, First Publication No. 2003-159254    (Patent Document 2) US Patent Application, Publication No. 2003/0236535A1